CVE-2025-11721

Memory safety bug fixed in Firefox 144 and Thunderbird 144

CVSS 9.8 CRITICALEPSS 0.3%CWE-119

Vexday Risk Score

28Low

SSVC decision (CISA)

Track

No exploitation signal → monitor

CVSS 9.8EPSS 0.3%KEV nãoPoC —Nuclei —Metasploit —Patch —

Lifecycle

14 Oct 2025Published on NVD

Recommendation: Monitor — no exploitation signal at the moment.

Memory safety bug present in Firefox 143 and Thunderbird 143. This bug showed evidence of memory corruption and we presume that with enough effort this could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 144 and Thunderbird 144.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

Mozilla · Firefox Mozilla · Thunderbird

References

https://bugzilla.mozilla.org/show_bug.cgi?id=1986816 https://www.mozilla.org/security/advisories/mfsa2025-81/https://www.mozilla.org/security/advisories/mfsa2025-84/